基于Http的通信
package com.example.httpgetdemo;public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); findViewById(R.id.button1).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { new AsyncTask(){ @Override protected Void doInBackground(String... params) { try { URL url = new URL(params[0]); URLConnection connection = url.openConnection(); InputStream inputStream = connection.getInputStream(); InputStreamReader isr = new InputStreamReader(inputStream, "utf-8"); BufferedReader br = new BufferedReader(isr); String line; while ((line = br.readLine()) != null) { System.out.println(line); } br.close(); isr.close(); inputStream.close(); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return null; } }.execute("http://fanyi.youdao.com/openapi.do?keyfrom=httpgetdemo1&key=1659546208&type=data&doctype=json&version=1.1&q=good"); } }); }}
通过Get和Post方式请求
MainActivity.java
package com.example.httpgetdemo;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;import java.util.ArrayList;import java.util.List;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.HttpClient;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpGet;import org.apache.http.client.methods.HttpPost;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import android.app.Activity;import android.os.AsyncTask;import android.os.Bundle;import android.os.Handler;import android.util.Log;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;public class MainActivity extends Activity { private String TAG = "http"; private String baseURL = "http://192.168.24.250:8084/test_web/NewServlet"; private EditText mNameText = null; private EditText mAgeText = null; private HttpResponse response = null; private Button getButton = null; private Button postButton = null; private TextView mResult = null; private Handler handler = null; private String result = ""; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // 创建属于主线程的handler handler = new Handler(); mNameText = (EditText) findViewById(R.id.name); mAgeText = (EditText) findViewById(R.id.age); mResult = (TextView) findViewById(R.id.result); getButton = (Button) findViewById(R.id.submit_get); getButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { new AsyncTask() { @Override protected Void doInBackground(String... params) { System.out.println("mGetClickListener"); Log.i(TAG, "GET request"); // 先获取用户名和年龄 String name = mNameText.getText().toString(); String age = mAgeText.getText().toString(); // 使用GET方法发送请求,需要把参数加在URL后面,用?连接,参数之间用&分隔 String url = baseURL + "?username=" + name + "&age=" + age; System.out.println(url); // 生成请求对象 HttpGet httpGet = new HttpGet(url); HttpClient httpClient = new DefaultHttpClient(); // 发送请求 try { // HttpResponse response = // httpClient.execute(httpGet); response = httpClient.execute(httpGet); // handler.post(runnableUi); System.out.println("response:" + response); showResponseResult(response); } catch (Exception e) { e.printStackTrace(); } return null; } }.execute(""); } }); postButton = (Button) findViewById(R.id.submit_post); postButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub new AsyncTask () { @Override protected Void doInBackground(String... params) { // TODO Auto-generated method stub System.out.println("mPostClickListener"); Log.i(TAG, "POST request"); // 先获取用户名和年龄 String name = mNameText.getText().toString(); String age = mAgeText.getText().toString(); NameValuePair pair1 = new BasicNameValuePair( "username", name); NameValuePair pair2 = new BasicNameValuePair("age", age); List pairList = new ArrayList (); pairList.add(pair1); pairList.add(pair2); try { HttpEntity requestHttpEntity = new UrlEncodedFormEntity( pairList); // URL使用基本URL即可,其中不需要加参数 HttpPost httpPost = new HttpPost(baseURL); // 将请求体内容加入请求中 httpPost.setEntity(requestHttpEntity); // 需要客户端对象来发送请求 HttpClient httpClient = new DefaultHttpClient(); // 发送请求 // HttpResponse response = httpClient // .execute(httpPost); response = httpClient.execute(httpPost); showResponseResult(response); } catch (Exception e) { e.printStackTrace(); } return null; } }.execute(""); } }); } /** * 显示响应结果到命令行和TextView * * @param response */ private void showResponseResult(HttpResponse response) { System.out.println("response:" + response); if (null == response) { return; } HttpEntity httpEntity = response.getEntity(); try { InputStream inputStream = httpEntity.getContent(); BufferedReader reader = new BufferedReader(new InputStreamReader( inputStream)); String line = ""; while (null != (line = reader.readLine())) { result += line; } // System.out.println(result); // mResult.setText("Response Content from server: " + result); MainActivity.this.runOnUiThread(runnableUi); } catch (Exception e) { e.printStackTrace(); } } // 构建Runnable对象,在runnable中更新界面 Runnable runnableUi = new Runnable() { @Override public void run() { // 更新界面 mResult.setText("Response Content from server: " + result); result = ""; } };}
Server端代码
import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * * @author Administrator */@WebServlet(urlPatterns = {"/NewServlet"})public class NewServlet extends HttpServlet { protected void proce***equest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); String username = request.getParameter("username"); String age = request.getParameter("age"); response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("Welcome! "); out.println(" Welcome my dear friend!"); out.println("Your name is: " + username + ""); out.println("And your age is: " + age + ""); out.flush(); out.close(); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.err.println("doGet"); proce***equest(request, response); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.err.println("doPost"); proce***equest(request, response); } @Override public String getServletInfo() { return "Short description"; }// }